CDKN2A and acute lymphoblastic leukemia: Genome-wide association studies (GWAS) of childhood acute lymphoblastic leukemia (ALL) have identified risk loci at several genes involved in B cell differentiation, including IKZF1, CDKN2A, ARID5B, CEBPE, GATA3, BMI1, and PIP4K2A [1–6].